Method of and apparatus for making tubing



w. J. woons METHOD OF AND APPARATUS FOR MAKING TUBING May 22, 1928;-

Filed. April 6, 1925 4 .0 4 $34422 W 2 w f Z W 1 3 a w .1 2 I w\ 2 1. 13,5. 6 a z 1 I 5 Patented May 2 9 UNITED PAT T OFFICE.

- WILLIAM J.

arnrspnor Ann ArrARArns roamanme TUBING.

Application filed April 6, 1925. Serial no. 21,162.

' This invention relates to the art of shap-.

-ing glass, and more particularly to making of very small bore,

glass tubing.

It is now customary to make tubing in four main ways: a rotating mandrel; (b)'by forming a blank by hand and then drawing it in a machine (c) by forming a blank by hand andthen drawing it by hand; andttl) by blowing it;

ina mold. Y

All tubing of other than one colorglass, of, other. than circular cross-section ,orbore," and all thick-walled tubing,

.ing kinds, i-smade by method (1)), method (0),01' method (cl) because theHrot-ating mandrel methodiis not adapted tothe formation of tubing of-this character.. Method oi large diameter, which is often referred .to as a cylinder. Consequently, all thermometer tubing, which customarily has a white stripe between the bore and the rear wall, as well as tubing having a-special cross-sectionfor, bore, all niscellaneous striped tubing. and all thicl'r-walled tubing, except such of the latter as is-made by method (at) has had to be made from a hand formed blank. This, however, requires highly skilled labor and makes the tubing which is formed therefrom quite expensive. Furahermore, the bore in such tubing, while accurate enough for many purposes, is not sufficiently accurate for some purposes, such as burettes, syringe barrels, etc., and has to 'be reground or otherwise treated to over come th'ese inaccuracies,

It istheret'ore an object, of this invention to provide a new and Improved process of.

making glass tubing that will be cheaper hand gathering. v It is another object to-provide amethod ofmaking tubing of uniform and accurate predetermined cross-section without marvering or other special treatment. a

It is a further object to provide a method of forming tubing with an accurate boreor v bores of any predetermined SIZQOI shape,

finished tubing.

and located at any desired position in'the It is a still further object to'provide a method of making tub ng in vwhichcolored (a) By flowing it around.

as well as some tubing of the forego- .is only practicable for ,making tubingfinished tubing.

wo'ons. or oonurne, NEW YORK, .A'SSIGNOR 'ro oomvmo emss wonxs'.

or oonmno, nnwyonx, .A oonrona'rxonor NEW YORK.

It is also an object to provide an appir rat-us for carrying out the above objects. W th the above and other objects in view, which will be apparent as'the description proceeds, I' have disclosed my invention in the following specification taken in connectlon with the accompanying draw1ngs,"1n

which I aFig. 1 is a plan'view of a suitable apparatus for carrying; out my invention; K

shown in Fig. 1; r Fig. .3 is a transverse 3-3 of Figs. 1 and 2, but showing certain section on'the line Y Fig. Qis a side elevation of-the apparatus parts in adilierent relation andglass in the mold;

. Fig. his a transverse section through the molten glass shown in Fig: 3 on the line 4-4 thereof before the preformed tubing has become incorporated with the molten glass toiorm an integral blank Fig. 5 isa corresponding sectionthrough the glass shown in Fig. 3, after the preformed tubing has become incorporate with the molten glass and set toform the dso' Fig. 6 is a'transve'rse section through a piece OFfin'ished tubing drawn from the blank whosev cross-section is shown in Fig.

Figs. 79 are transverse e ioie'6rresponding to those shown in ]Figs 4.- 6, but taken through masses of glass having a moditied shape of'bore, a bore"placed ata different position inthe glass, and a colored white stripe;

preformed tubing 10 then unites to the molten glass 13 and forms a blank 14 which ished tubing and is therefore provided with inventionconsists in heating a-piece .ofpreformed tubing 10, attaching it to any suitable holder 11, andinserting it in a mold 12 filledgwith molten glass 13. The.-

stripe interposed:betweenjthebore and'a a bore 16 whose shape is the same as that of the bore in the tubing it is desired to form, and whose size is proportionate to the desired size of bore in the finished tubiiig, as well as any colored stripe or stripes*it"is desired to have present in the finished tubing.

As illustrated in Fig. 4, the bodyof the preformed tubing consists of clear glass 17,

on one side of which there is a stripe of white glass 18, to form .the white stripe which is usual in thermometer tubing. The molten glass 13 is shown as being clear glass and, afterthe adhesion of the preformed replaced by the typc'of punty customarily used in drawing tubing.

In Figs. 1-3, however, it have disclosed a suit-able and preferred form of apparatus for convenientl carr in out m new meth-.

0d. In these figures, 20 represents a suitable frame work consisting of a base member 21, a lower member 22 and an upper member 23. The members 22 and 23 may be of any de sired shape but are herein shown as channel irons which are adjustably secured together by bolts 24 in mating openings 25 in the channel irons, whereby the height -of the framework may be altered as desired. The base member 21 has a series of angle irons 26 which are, bolted or riveted together to form a unitary construction and are secured to the lower member 22. Crossed braces 27 are provided to secure thechannel irons 22 firmly together; I

The mold 12 is preferably assembled so as to simulate a one piece mold although. as shown herein, for convenience of 1nanufacture it may be made of two or more parts such as the body 29 and bottom 30 which are secured together by the bolts 31. As indicated in Figs. 1 and 3, the bottom 30 is perforated at 32 for a purpose to be described hereinafter.

The mold 12 is provided with trunnions 33 and is secured to the frame work 20 by pivot pins 34 which pass through the framev work to enable the mold to be freely swung thereon.

The holder 11 is preferably of the type indicated in Figs. 13, and consists of a slotted block 40 which is threaded on a supporting arm 41 mounted in a suitable guide 42. The latter is preferably bolted Then, as the glass I starts to set, the sticking up punty may be ma am.

or otherwise secured to one of the channel irons 23 adjacent its upper end and is provided with a stop 43 which is either integral with the guide or securely attached thereto. To limit the movement of the. arm 41 in the guide 42 and to regulate the path of the arni 41 relative to the mold 12 ll provide the arm with a collar 44 having a set screw 45, I

and with a projecting finger 46 for engagement with the channel iron 23 and the stop 43. By adjusting thearm to the desired position in collar 44, and tightening the set screw 45, the height and lateral position of the preformed tubing 10 can easily be adjusted With reference to the mold, since the descent of the collar is limited by its contact with the guide 42, and the lateral travel of the arm 41 is limited by the contact of finger 46 with channel iron 23 and stop 43.

To receive the preformed tubing 10 in the block 40, the latter is provided with a slot 47 of sufiicient size to permit the reception of various sizes of tubing. The block'is also provided with an adjustable stop 48 which is pulled inwardly by a spring 50 that is'attached to pins 51 and 52 carried, respectively, by the stop 48 and the block 40. The spring 50 is of such a tension that it pulls the stop 481into contact with the tubing 10 and holds the latter firmly against the inner side of the slot 47 v To conveniently regulate the radial position of the tubing 10 with reference to the contour of the mold, the block '40 and arm mold 12 is substantially filledjwith molten glass13. outwardly a suflicient distance to allow the insertion of the end of a piece of preformed and heatt d tubing 10, having the desired characteristics. and is then released, causing,

Stop 48 on the block 40 is pulled the tubing to be retained in the slot 47 by.

the pressure of the spring 50. Arm 41 is then lifted from the full line position indicated in Fig. 1 until it is high enough so that the tubing 10- will clear the mold 12, swung inwardly to the dotted line position (Fig. 1) where the tubing is above its desired position in the mold, and lowered thereinto. A section through the glass at this time is shown in Fig. 4, and a corresponding section, after the preformed tubing has become incorporated with the molten glass and the latter is set to form the I the wall thereof, and with a stripe ofwhite as is customary in thermon'n 'eter tubing.

blank, is shown in- Fig. 5. As indicated the latter figure, the clear glass then forms a homogeneous mass and the line of juncture "sired'tubing 15, shown in cross-section in F ig. 6.

jTo form astripe or stripes of colored glass in the'finished tubing it sary to start with a piece of preformed tub,- ing having. the desired stripe or stripes therein, of a size proportionate to the destripe or stripes will be imparted to the tinished tubing in the manner indicated above. Furthermore, by suitably choosing the shape and size of the bore of the preformed tubing, the resulting tubing will have a bore of the shape and size desired.

In Figs. 7-9, I'have illustrated threesteps n the manufacture of such a modified form of tubing. In Fig. 7., 7O designates. the preand apparatus,

formed tubing which is shown as being of oval cross-section and provided with an oval bore 71 the" preformed tubing being inserted in the mold in such a position that the bore 71 will be back of the center C of theblank. The preformed tiibii'ig'is also provided with a stripe of colored glass 72, for example red. adjacent to the bore and forming part of glass 73 such This is shown as embedded in 74, corresponding to the glass clear glass body of the preformed tubing,

forming the in a position mass of glass 74, to increase the magnification of '-the indicating liquid which will be used in the finished thermometer. In Fig.

8 there-is indicated a corresponding section through the glassi l after the preformed-tubing has become incorporated -with thomolten glass and the line of juncture eliminated. This is then drawn into the finished tubing 75. a section through which is indicated in Fig. 9. As indicated in this figure, the bore 71 of the colored stripe 72 forms part of the wall of the'bore, and an additional stripe 73 is intGIDOSGcl between the stripe 72 and the outer surface of the tubing.

It will be apparent that the stripe of White or other color glass may be applied is only neces'-.

back of the center C of thefinished tubing is oval and is back 0f the center, C of the finished tubing 75, a I I preformed tubing. attaching it to'a holder.

vided with a cavity 80 which is of such a shape the-tit will give the blank ashape suitable for foriiiing'the; familiar leris from; tubing. It'will be understood that in the formation of round or other shaped tubing the cavity 80 will be modified accordingly.

It will therefore be apparent that my method results in the production of a superior grade of tubing, owing to the fact that'the bore isaccurate and uniform, being size of the bore determined by the. shape and the in the-preformed tubing instead of by individual blowing'ofthe bore in each blank. It also results in a muchsiinplei" and cheaper method of foriniiigtl'ie tubing, since the blanks can he made byrelativclyunskilled theglass inthe present method of making theblanks, and provides asimple and cfiec tire way of imparting special configurations, such as that required for forming lens front tubing, to the exterior ofthe blank without a marvering operation.

Other modifications in my new method .within the scope of the .followingclaims, will occur't'o those skilled in the fllgt. i I claim: I 2 1. The method of making tubing which comprises the steps of heating a piece of labor instead ofthe highly paid labor which I is required to successfully gather and marver previously. drawn tubing, inserting it-in a mass of molten glass, and drawing the blank thus formed into tubing of the desired size.

2. The method of making tubing which comprises the steps of heating a piece of previously drawn tubing, attaching to fa holder, inserting thistubing in a mass of molten glass, and'drawing the blank thus formed into tubing of the 'dcsired size. j;

3. Themethod. of making tubing which comprises the steps of heating a piece of preformed tubing. attaching it..to a holder, supplying a charge of molten glass to a inold whose configuration conforms to the desired shape ofthe blank, inserting the tubing. in this moltenglass. allowing it to set, and

drawing the blank thus formed into tubing:

of thedcsiretl size.

4. The method of making tubing which comprises the steps of heating a piece-yo supplying a charge of molten glass to a inogd whose configuration -onf orms to the desir .d

shape of the blank. inserting the tubing in this molten glass. 'leaving ,the preformed.

to a mold having a shape corresponding to the proper shape of a blank for forming lens front tubing, inserting the tubing in this glass, and drawing the blank thus formed into tubing of the desired size.

6. The method of making striped tubing which comprises the steps of heating a piece of previously drawn tubing containing a stripe of the desired-character, attaching it to a holder, inserting this tubing in a mass of molten glass. and drawing the blank thus formed into tubing of the desired size.

7. The method of making tubing having a predetermined and accurate bore which'comprises the steps of heating a piece of previously drawntubing containing a bore of the same shape as that desired in the finished tubing. but of a size sufficiently larger than that of the finished bore to' allow for the subsequent drawing, inserting this preformed tubing in a mass of molten glass, and drawing the blank thus formed into tubing of the desired size.

S. An apparatus for use in making tubing, comprising a mold provided with a cavity of the shape of the desired blank, and means for suspending a piece of previously drawn tubing therein.

9. An apparatus for use in making tubing, comprising a mold provided with a cavity of the shape of the desired blank, means for ."?i'1pporting a piece of preformed tubing therein, and means for regulating the posi.- tion of the preformed tubing 1n themold cavity so it will be incorporated in the fin-' ished tubing blank at the position it is desired to have the bore occupy.

10. An apparatus for making tubing blanks, comprising a mold provided with a cavity of the shape of the desired blank, means for exposing the head of a punty in the mold, and means independentofthe punty for supporting a piece of previously drawn tubing therein.

11. An apparatus for making tubing blanks, comprising a mold provided with a cavity of the shape of the desired blank,

-means for-exposing the head of a punty in the mold. means for supporting a piece of 'prtdormed tubing therein, and means for formed tubing with reference to the cavity in the mold.

13. An apparatus for making tubing blanks, comprising a frame work, a mold supported thereby, a recess in. the mold, a punty inserted through said recess with its head exposed in the mold, a holder for supporting'a piece of preformed tubing, means for controlling the position of the holder with reference to the mold, andmeans for adjusting the position of the preformed tubing with reference to the cavity in the mold.

14. An apparatus for making tubing blanks, comprising a frame work, a mold pivotally supported tl1ereby,-a recess in the mold, a punty inserted'through said recess with its head exposed in the mold, a holder for supporting a piece of preformed tubing,

and means for regulating the position of the preformed tubing with reference to the cavity in themold. Y

15. An apparatus for use in n'iaking tubing, comprising a mold, a frame work supporting the mold, a holder to support a piece of preformer tubing, and means to permit the raising, lowering and swinging of the holder.

16. An apparatus for use in makin tubing, eomprisin a mold, a frame wori sup-. porting the m0 (1, a holder to supportapiece of preformed tubing, means to permit the raising, lowering and swinging of the holder, and means for adjusting the position of the holder with reference to said other means. H

17 .-An apparatus for use in making tubing, comprising a mold, a frame work supporting the mold, a holder to support a piece of preformed tubin means'to permit the raising, lowering an swinging of theholder, and means for limiting the lateral and downward movement of the holder.

18. An-apparatus for use in making tubing, comprisinga mold, a frame work supporting the mold, a holder to support a piece of preformed tubing, said holder being provided with resilient means for retaining the tubing therein, and means to permit the raising, lowering and swinging of the holder.

19. The. method of making tubing which consists in gathering glass on the end of a blow pipe, shaping it into a blank, drawing it out into tubing, inserting a predetermined length of said tubing into a mold, filling the remainder of said mold with molten glass, and drawing the blank thus formed into tubing of the desired cross section.

WILLIAM J. oons. 

